1. Field of the Invention
The present invention relates generally to implantable medical devices. More specifically, the present invention relates to a reconfigurable digital network for use in an implantable medical device.
2. Background Art
An active implantable medical device is an apparatus, driven by a power source, which is implanted in a patient to monitor, detect, and possibly affect biological signals in the patient. Active implantable medical devices include, but are not limited to, implantable cardiac devices, implantable pressure transducers, and implantable drug delivery devices. The term “implantable medical device” or simply “IMD” is used herein to refer to any active implantable medical device known in the art.
Current IMD hardware platforms, using general purpose processors, are limited in their capability of performing general signal processing algorithms. Such a limitation is due to the fact that the longevity requirement of an IMD requires tight constraints on the number of clocks cycles and processing operations an IMD processor can perform. In other words, attempting to run very specific signal processing algorithms, for example, algorithms that perform many numerical computations on data, on current IMD processors, is a very inefficient use of the IMD's power. General purpose processors, however, do have the advantage of being highly programmable and reconfigurable.
To perform specific signal processing algorithms, it is well known that hardware designed specifically for the algorithm is more power efficient. Dedicated algorithm hardware, however, is not as reconfigurable as general purpose hardware. As such, dedicated algorithm hardware is suitable for only its dedicated function, but cannot be reprogrammed to perform different algorithms. What is needed is an IMD having a hardware architecture which can perform specific signal processing operations in a power efficient manner, while maintaining the reconfigurability of general purpose IMD hardware.